In a new study published in the journal Science Translational Medicine, lead researcher Praveen Arany and colleagues detailed how they used focused laser light therapy on rats to stimulate the growth of lost dentin, the calcified tissue that comprises teeth. They noted that if the therapy proves effective in humans, it could potentially eliminate the need for crowns, fillings and other complex dental operations in the future.

Since the dawn of medical laser use in the late 1960s, doctors have been accumulating anecdotal evidence that low-level light therapy can stimulate all kind of biological processes including rejuvenating skin and stimulating hair growth, among others. But interestingly enough, the same laser can be also be used to ablate skin and remove hair—depending on the way the clinician uses the laser. The clinical effects of low-power lasers have been subtle and largely inconsistent. The new work marks the first time that scientists have gotten to the nub of how low-level laser treatments work on a molecular level, and lays the foundation for controlled treatment protocols.